Precisely calibrated gas-metering devices are commonly used in the medical, emergency and home health care industries for delivering oxygen to patients in need thereof. Nearly all regulators are attached to a high pressure oxygen tank via standardized mechanical connections set forth in the Compressed Gas Associations standards.
Millions of people suffer from chronic obstructive pulmonary disease. Sixty percent of them are treated and receive supplemental oxygen in their homes. Ambulatory patients are provided with portable oxygen systems. The most common system consists of aluminum or steel cylinders ranging in capacity from 160 to 660 liters containing oxygen at 2000 psi. The cylinder is fitted with an off/on post valve to which an oxygen regulator is attached. The regulator reduces the gas pressure from 2000 psi to 50 psi typically. In addition, most regulators include a flow control section that meters the gas to the patient at a prescribed or desired flow rate. Nearly all of the regulators are fitted with an external pressure gauge that displays the pressure within the cylinder at all times. The gauges are fragile, and even though fitted with protective rubber surrounds, are easily broken since the protrude from external surface of the regulator body. When a gauge is broken, it is necessary for the home care provider to make an unscheduled visit to the patient's home to replace the regulator. The large number of unscheduled visits is a large expense to the home care provider industry.
Many regulator devices are presently known that provide such functionality. A variety of such devices are manufactured by Flotec, Inc. of 7625 West New York Street, Indianapolis, Ind. 46214. Many styles of regulator products are produced in the U.S. One common style of regulator is the "unibody" regulator design. The unibody design is typified by a single substantially cylindrical assembly including a yoke at one end for mounting the regulator on a high pressure tank and a regulator body integral with the yoke that includes a pressure reducing section and a flow control section. Typically, these devices also include a pressure gauge that is screwed into a threaded hole in the outer surface of the cylindrical body.
Oxygen tanks onto which the pressure regulator/flow control devices are attached are quite heavy and easily tip over. When an oxygen tank tips over it is not uncommon for the pressure gauge attached to the external surface of the regulator device to suffer damage. An improvement in regulator design that minimizes the likelihood of damage to the pressure gauge is desired.
Further, pressure regulator/flow control devices are constructed with machined metal parts that are subject to surface wear. Very fine particles of metal are created when the internal moving components of the regulator make contact with each other. It is thus a further desired feature to minimize the likelihood that such fine metal particles are introduced into the gas flow provided to the user of such devices.
Therefore, an improved compressed gas regulator/flow control device with an internal gauge and improved particulate filtering is desired.